Has Anyone Installed Their Own Split System AC?

[Travelover]

I'm thinking of replacing my split system AC system myself by buying through a place like Alpine and having a contractor do the refrigerant part. The system is a 1972 Sears (really) set up with an A coil in the furnace and the compressor / condenser on a slab outside. Amazingly, the current system works very well, but sucks power and is so old that it could die at any time.

I'm curious if I can expect a hard time from the building inspector or have difficulty getting a contractor to do a partial install. Of course, I'd need the old refrigerant pulled out before I disassembled the old system plus have the new system evacuated and the new refrigerant installed. Beyond that, I think that I could do it all myself.

Thoughts, experiences to share?

 

[Larro Darro]

No experiences, but I think if the AC guy will sign off as the contractor, you shouldn't have a problem with the inspector.

Changing it out is a good idea. They say that replacing anything over 10 years old, the energy savings will pay for the new equipment. Not sure how long a time frame, though. Good luck.

Larro

 

[TnAndy]

I've installed two "mini" split systems in my house over the years....the ones that have no ductwork, just a set of lines from the outdoor unit to the indoor unit. Both Mitsubishi units.

Basically, you'd be doing the same thing, since you already have the ductwork in place. I found my AC guys to evac system and turn the pre-charged gas loose on Craig's List. I told then in advance what I was doing and what I wanted.....both of them charged me $100 bucks, which I thought was fair enough for them to come out with the vac pump, do that, and check the gas pressure after release.

Not that this applies in your case, but I LOVE the mini splits.....especially this new one. 23 SEER and so quiet on low, you can't even tell it's running.

 

[Ed of all trades]

I was a hvac installer for a number of years, I installed and a teck. would charge the sustem. It will depend on how much the systems are alike and how much you can do. It could likely need new plenums made, (boxes the unit hooks to) or other problems. Most hvac shops could make it for you though.

 

[Travelover]

I was a hvac installer for a number of years, I installed and a teck. would charge the sustem. It will depend on how much the systems are alike and how much you can do. It could likely need new plenums made, (boxes the unit hooks to) or other problems. Most hvac shops could make it for you though.

Ed, is there a reason why I couldn't just replace the A coil in the updraft furnace plenum with another just like it? As I mentioned, it works fine and cools the house well, it is just ancient.

 

[hilltopdw]

I installed mine, had a licensed contractor pull vacum and level refrigerant, mine came precharged actually he had to take a little out. (depends on length of line set.) piece of cake. I love mine you cant even here it run, I'm using it in my recording studio.

 

[murphy1244]

The change to 410A will have a much larger coil to use in the Furnace.

 

[murphy1244]

I installed mine, had a licensed contractor pull vacum and level refrigerant, mine came precharged actually he had to take a little out. (depends on length of line set.) piece of cake. I love mine you cant even here it run, I'm using it in my recording studio.

Most sets are precharged for 25 feet some for 15 feet.

 

[kenmac]

The change to 410A will have a much larger coil to use in the Furnace.

Yes, and sometimes are a problem if, you don't have height. Most are about 25-30'' tall. It's also very important to either replace the old refrigerant lines or, make sure the old lines are very, very, very clean .The new 410A refrigerant doesn't like dirty refrigerant lines...Pull a 400 micron vacuum

 

[murphy1244]

Yes, and sometimes are a problem if, you don't have height. Most are about 25-30'' tall. It's also very important to either replace the old refrigerant lines or, make sure the old lines are very, very, very clean .The new 410A refrigerant doesn't like dirty refrigerant lines...Pull a 400 micron vacuum

The lines must go as the pressure will be increased a great deal and will find any and all weak spots on the old lines.

 

[kenmac]

The lines must go as the pressure will be increased a great deal and will find any and all weak spots on the old lines.

I agree,100% Although it's not always possible. I've had cases where it was impossible to replace the lines and had to use the old stuff. When I do have use the old line sets, I test with nitrogen at higher pressures to see if it holds.. To be honest , some of the old copper is thicker than the new stuff. With higher pressures with 410A, it's best to replace the line sets if at all possible

 

[murphy1244]

I agree,100% Although it's not always possible. I've had cases where it was impossible to replace the lines and had to use the old stuff. When I do have use the old line sets, I test with nitrogen at higher pressures to see if it holds.. To be honest , some of the old copper is thicker than the new stuff. With higher pressures with 410A, it's best to replace the line sets if at all possible

Its the connections that get added on that I worry about but I agree its sometimes hard to replace a line set that's been stuccoed in.

 

[Dr Dave]

If the ac is that old, how about the furnace, or air handler? I would replace both at he same time. A package system will be much more efficient and trouble free.

I replaced my hvac unit about 10 years ago for $1800 its paid for its self 3 times in enegy savings!

Removed and installed in a weekend, the line set had to be silver soldered, compressor unit was precharged. You have to pull a vacuum, check for leaks and adjust the charge, I did my own since I had the equiptment and im certified.

My stepdad installed his own also, and had the final connections and charging done by a contractor for leaks$250
His system was 2k delivered to his home. He reseived bids from 8-9k to have a system installed.

Dave

 

[murphy1244]

Those R-22 units are long gone replaced by R410A which bumped up the pressures big time.

 

[kenmac]

Those R-22 units are long gone replaced by R410A

Which will Possibly be replaced by 407C

 

[murphy1244]

Which will Possibly be replaced by 407C

You think? how soon ?

 

[kenmac]

You think? how soon ?

Don't know when it will be, but a replacement for 410A refrigerant is in the works. Talk is it will more than likely be 407C

 

[Travelover]

If the ac is that old, how about the furnace, or air handler? I would replace both at he same time. A package system will be much more efficient and trouble free.
..........
Dave

The furnace is just 3 years old. In the past I've almost never needed AC, thus the 1972 model lasting so long. These days we seem to be having more week long 90's weather with high humidity. Knowing this now, I should have done a package deal.

Those R-22 units are long gone replaced by R410A which bumped up the pressures big time.

Alpine still has R-22 units for sale, though I hate to buy something that will have super expensive refrigerant in a few years.

Example: Goodman GSC130301-DRY 2.5 Ton, 13 SEER Condenser, For R-22 Refrigerant Use (Unit is Uncharged)

I know there is a raging controversy over the Goodman brand, but for me and my usage, I think it would be good enough.

 

[Travelover]

The change to 410A will have a much larger coil to use in the Furnace.

Good tip - this is exactly what I was wondering.

 

[brin]

The furnace is just 3 years old. In the past I've almost never needed AC, thus the 1972 model lasting so long. These days we seem to be having more week long 90's weather with high humidity. Knowing this now, I should have done a package deal.

Alpine still has R-22 units for sale, though I hate to buy something that will have super expensive refrigerant in a few years.

Example: Goodman GSC130301-DRY 2.5 Ton, 13 SEER Condenser, For R-22 Refrigerant Use (Unit is Uncharged)

I know there is a raging controversy over the Goodman brand, but for me and my usage, I think it would be good enough.

I have used Goodman HVAC units for over 20 yrs. in my home and rental properties...I have had nothing but good service from them and for me they have just as dependable as the name brand units....I would buy another one if the need arises.